Since rigging fails inside of the end fittings where they cannot be inspected, prudence dictates that standing rigging be replaced every seven years for boats sailed in salt water, every ten years for those sailed in fresh water.

You should “pre flight” and “post flight” your rig before and after every sail. Every time you sail in more wind than you have sailed in previously with your new rigging, it should be re-tuned.

Yes. Many world cruisers use this type of fitting on both ends of their standing rigging. If anything happens en route to Tahiti, it can be repaired aboard without special tools. Production builders don't use them because it would add tens of thousands of dollars to their annual costs.

Maybe. The user installed end fittings are more expensive. But you’re only buying one per shroud. You also save the cost of shipping your old rigging and potentially hundreds of dollars in yard fees. If you avoid unstepping the mast or hiring a rigger you’ll save much more.

Use either a bypass style cutter designed for stainless or an appropriate cut-off wheel on a Dremel tool. Do not use a bolt cutter that drives a blade into an anvil. It will munch up the end of the wire terribly.